Advances in technology have resulted in smaller and more powerful computing devices. For example, there currently exist a variety of portable personal computing devices, including wireless computing devices, such as portable wireless telephones, personal digital assistants (PDAs), and paging devices that are small, lightweight, and easily carried by users. More specifically, portable wireless telephones, such as cellular telephones and Internet Protocol (IP) telephones, can communicate voice and data packets over wireless networks. Further, many such wireless telephones include other types of devices that are incorporated therein. For example, wireless telephones can also include a digital still camera, a digital video camera, a digital recorder, and an audio file player. Also, such wireless telephones can process executable instructions, including software applications, such as a web browser application, that can be used to access the Internet. As such, these wireless telephones can include significant computing capabilities.
Digital signal processors (DSPs), image processors, and other processing devices are frequently used in portable personal computing devices that include digital cameras, or that display image or video data captured by a digital camera. Such processing devices can be utilized to provide video and audio functions, to process received data such as image data, or to perform other functions.
One type of video processing involves filtering, which may be applied to enhance the quality of a decoded video signal. The filter can be applied as a post-filter, where the filtered frame is not used for prediction of future frames, or as an in-loop filter, where the filtered frame is used to predict future frames. A filter may be designed by reducing an error between the original signal and the decoded filtered signal. Similarly, to transform coefficients, the coefficients of the resulting filter may be quantized, coded, and sent to the video decoder. More precise quantized filter coefficients may enable better performance. However, as precision of quantized filter coefficients increases, a number of bits required to transmit the coefficients may also increase, with a corresponding impact on network resources, data delivery rates, or both.